Bearing boring apparatus



ct; 6, 1936.. R, W. HENNINGS 2,056,671

BEARING BORING APPARATUS Filed March 13, 1954 J4 6' .9?. Invention.

Patented Oct. 6, 1936 UNITED STATE-s BEARING` BORING APPARATUS Ralph W. Hennings, FarmingtonQMane Application Marchl 13, 1934, Serial No. 715,310

7 Claims. (Cl."77--58) This invention relates to apparatusfor boring andY sizing shaft bearings and is particularly concerned with, although not necessarily restricted to, boring and sizing the crank shaft Abearings Vof `5'? automobiles or internal combustion engines to fit the shaft after the bearings have been re-babbitted-or renewed.

Bearing boring apparatus usually includes a boring bar or shaft which is supported rotatably 10 in the axis of the bearings and has a cutter thereon which is rotated by the boring bar in cutting engagement with the bearing.

One of the objects of the present invention is the provision of a'cutter support or head wherein l5 the adjustment of the cutter, or the amount of cut that the tool is to make, can be readily and accurately set andy if desired, measured prior to making the cut.

A further object is the provision ofa cutter '20 .support wherein the cutter ory cutting tool is 'clamped against the surfaceof the cylindrical boring bar and extends tangentially thereof and vthe radial distance of the cutting edge of the tool to the axis of the boring bar, which determines E5 the diameter of the crank shaft bearing, is varied by rocking the tool on the boring bar-and clamping it inY any set adjustment.

Another object of the invention is the provi'- sion of improved adjustable supports for posi- '30 tioning the boring bar coaxially with the'bearings and for supporting it rotatably and longitudinally movably inposition.I 1 Y 1 A yet further object is generally to improve the construction and operation of bearing1 boring ap- .'35 paratus. f

4.5 f Fig. 5v is a side elevation of the cutter support.

Fig. 6 is a section taken along line --G of Fig.5. The invention is herein illustrated forthe purpose of boring or finishing the crank-shaft bearings I0 of' an internal combustion engine cylin- /50 der and crank case block I2 having four cylinders and three bearings although'the number of cyl- .inders and bearings is of no importance to the 1 presentv invention.Y l

A. cylindrical boring-bar I 4 is extended coaxially .55 f of the bearings' lil and isy supported rotatably by PATENT oFFicla-v end supporting yokes I6 and an intermediate yoke I8. All yokes have the. central archesA 20 within which the cutter head and its tool areadapted to rotate at times. The intermediate yoke has oppositely` directed feet 22` which rest upon the opf5' posed anges. 24` of the cylinder block, theA feet havingslots 26 therethrough through which bolts 28 are passed toclamp the yoke to the block, the slots being elongated to permit the yoke to be positioned in line with the bearing axis. Theend 10 yokes I6 have .opposed arms .30 provided with longitudinally extended slots 32 through which bolts 34 are passed and are screwed into the ends of channelshaped blocks 36 secured on. and adjustable lengthwise. ofthe cylinder block anges `l5 .24. All yokes are long. enough for clamping, to the flanges of engines havinglarge differences in crank case wid-th. The boring bar I4 isrotatable and movable axially. in self-aligning spherical bearings 38 carriedr by. and disposed between '20 plates. 48 andbearing caps 42 secured removably to saidA plates, said plates being secured to the yokes I6 and IvI8 by bolts .44 located in vertically elongatedslots in rsaid plates,. accurate vertical .positioning lof the plates beingelected by ad- 52'5 justing screws 46 and lateral adjustment being .eiected by adjusting screws 48 bearingagainst the opposite sides ofthe plates andscrewthreaded in ears 50'of the yokes.

A cutter'hea-d 52 carrying .a cutter blade or .1.30 tool 54 is clamped to the boring bar andis rotated and advanced by the bar into cutting engage.- ment with the bearings IU. While but one. cutter Vhead is here show non the bar,.more can be provided if desired. .35

The boringbar is advanced axially at the same time it is rotated'by. an externally screw-threaded feed sleeve 56 held releasably in clamping engagement with the bar in any selected position axially of said bar; by a nut 58 which compresses ..40 the longitudinally slotted end of the sleeveinto `frictional engagement with the bar. Said feed V*sleeve is screw-threaded into" one end of a vertitwohalves of' the collar are retained removably in assembled position n engagement with the feed sleeve by 'an inverted U-'shaped spring clip 64,160

the free -ends'of which bear inwardly against the parts oand are anchored in the collar so that it can not rotate, rotation of the clip being prevented by the post 'interposed between the legs ofthe clip and` removably screw-threaded into '55 82 -of the tool.

Vis caused to project farther beyond the axis of the plate 40. After one cut has been taken the boring bar may be rapidly returned to the beginning of a second cut by spreading apart the two halves of the collar sufficiently to disengage the feed sleeve and then pulling the bar back. The ends of the bearing can be machined by removing the post 66, so that the collar can rotate on the iiange 62 with the rotation of the boring bar and cutter without advancing the cutter head axially. The cutter can be set to remove the desired -depth of material by a suiiicient rotation of the feed sleeve 56, the pitch of the screw threads thereof being known.

The cutter head 52 is illustrated in detail in Figs. 5 and 6. Said hea-d includes a sleevel which is axially movable on the boring bar intoV any desired position in which it is thereupon clamped to the bar.

bar and preferably has a resilient grip on the bar, since the sleeve is not circumferentially continuous. The sleeve is provided with enlarged confronting heads 'l2 and a reduced or thinner intermediate cylindrical section 14. The tops of the heads are terminated under the periphery of the boring bar so that a peripheral portion |4a of the cylindrical bar protrudes beyond and between said heads in the side opening of the sleeve between the heads. A semi-cylindrical yoke or cradle 16 overlies the protruding portion` l4a and has slots or apertures 18 in Yits ends in which the heads 12 of the sleeve are loosely located. Said yoke has a transverse slot or groove in which the cutter blade or tool 54 of any suitable character is loosely seated. Asherein illustrated the tool comprises a straight rectangular bar having flat sides and a cutting end 82 of suitable `character. The yoke has integral bridges 86 which overlie the flat back faces 88 of the sleeve heads ,'12 and clamping screws 90 are screw-threaded in said bridges and bear upon said flat faces thereby ,drawing the yoke and the cutting tool toward the boring bar and, when tightly setup, clamping'the cutting tool 54 between the bottom wall 82 of the yoke and the exposed portion of the cylindrical boring bar. The same clamping action also secures the. cutter head .against rotation-and axial movement on the boring bar. Thus the cutting end .82 of the cutting tool 54 is held secured in extended position, tangentially on the boring bar,

Vto take a cut in the bearing portionV 10a of the bearing I0. vThe diameter of the cut, that is tol say, the radial distance of the cutting edge 82 from the axis of the boring bar, can be varied .easily and accurately by backing-offone screw 90 an-d screwing down the opposite screw. If, for instance, after the surface Illa has been bored, it is desired to take another cut, say to the dotted surface I 0b, the left hand screw 90, Fig. 6, is backed-oit and the right hand screw is advanced. This operation causes thecutter 54 to rock-on the exposed .portion 14a of the boring bar and to -advance or roll on the boring bar toward the left so that the point of contact between the tool and the bar is moved vaway from the cutting edge Thus the cutting end of the tool the bar and the-radial distance of the cutting edge from the axis of the bar thereby is increased. This is apparent from aninspection of the full -and dotted line positions of the cutter head and the tool. If the radial distance is to be shortened the reverse operation istaken.V The adjustment of the tool as above described `can be made with- The sleeve is of substantial i axial length so that it has a good bearingon the fl Vhlead having a passage therethrough for a cylindri- Y cal boring bar and a transverse passage for a cutter blade, the passages being open into each other `and so arranged that a peripheral portion of the boring bar is exposed in said cutter blade passage, and clamping members disposed on opposite sides of the exposed peripheral portion of the cylindrical boring bar and arranged to force the cutterblade against' said exposed portion of the boring bar, said clamping members being disposed on opposite sides of the line of contact of the boring bar and cutter blade and being adjustable toward and away from the cutter blade so that by backing-off one and advancing the other clamping member the cutter blade can be rocked on the peripheral portion of the boring bar and the position of the cutting end of the cutter blade varied.

2. Bearing boring apparatus comprising a cutter head including a sleeve having acylindrical boring bar passage therethrough and opposedrfr'ee heads on opposite sides of the passage and between which the boring bar is adapted to project, a yoke disposed transversely of said bar passage having apertures in its ends adapted to receive said heads and having a cutter blade slot confronting said heads that is transverse of and opens into said boring bar passage, a cutter blade in said slot and upon the boring bar, and clamping `members'carried by said yoke on opposite sides of the line of engagement betweensaid cutter blade and boring bar and each clamping member bearing on a separate one of said heads to force said yoke against said cutter blade on the boring bar and each :separately adjustable toward and away from said cutter blade slot, the arrangement being such that the cutter blade can be rocked upon the boring bar by the adjustment of said clamping members to vary the cutting radius of the cutter blade.

3.' Bearing boring apparatus comprising a cutter head including a clamping sleeve having free ends and an axial passage therethrough for the cylindrical boring bar, the sleeve having an opening in one side and from end to end thereof between its ends through which a part of the periphery of the boring bar is adapted to project, heads on the free ends of said sleeve on opposite sides of the sideopening, a yoke overlying said opening having a cutter blade slot which traverses the side opening and apertures in which said heads are loosely located, a cutter blade in said slot and.` upon the boring, and clamping screws screw-threaded in said yoke at said apertures and adapted to bear on said heads to force said yoke against said cutter i and having an opening in its side wall through which a peripheral portion of said boring bar projects, heads on said sleeve on opposite sides of and below said exposed periphery, a yoke overlying said exposed periphery and having apertures in its ends in which said heads are loosely located and a cutter blade slot which traverses said exposed periphery, a cutter blade in said slot bearing upon said exposed periphery, and clamping members engaged between said heads and the ends of said yoke and clamping said cutter blade against said boring bar, said clamping members being separately advanceable and retractable so that by advancing one and retracting the other clamping member said cutter blade can be rolled upon said boring bar and the radial distance of the cutting end of said cutter blade from the boring bar axis can be varied.

5. Bearing boring apparatus comprising a cutter head arranged for mounting on a rotatable cylindrical boring bar, said cutter head comprising a sleeve slidable axially on the bar having a bladereceiving passage and an opening through its side wall into said passage through which opening a peripheral portion of the boring bar projects and heads projecting laterally from said side wall on opposite sides of said opening below the projecting part of the boring bar, a semi-circular yoke overlying said opening and having apertures in its ends in which said heads are located loosely, said yoke having a cutter blade slot which is disposed transversely of said boring bar passage and is adapted' to receive, a cutter blade in said slot bearing upon the projecting periphery of the boring bar, and clamping screws threaded in the ends of said yoke and bearing separately on said heads to clamp the cutter blade upon the boring bar.

6. Bearing boring apparatus comprising a cylindrical boring bar, a cutter head thereon, a cutter blade carried by said head extended transversely of said boring bar and bearing tangentially on the periphery thereof, and cutter blade clamping devices carried by said head and disposed on opposite sides of the line of contact of said boring bar and cutter blade and acting in a direction to force said cutter blade against said boring bar, said; clamping devices being separately adjustable so that one can be advanced and the other retracted for rocking said cutter blade upon said boring bar to vary the cutting radius thereof.

7. Bearing boring apparatus comprising an adjustable cutter supporting head arranged for mounting on a rotatable cylindrical boring bar, said cutter head comprising a cutter blade supporting yoke, a cutter blade in said yoke having a ilat surface adapted to be disposed transversely of and in contact with the cylindrical periphery of the bar, a clamping sleeve which has a boring bar receiving passage between its ends, the passage being laterally open between the ends so that a portion of the periphery of the bar isl exposed therebetween and under the yoke, and clamping devices engaging both ends of said sleeve and said yoke on opposite sides of the boring bar and operable to force the at surface of said cutter blade against the exposed portion of the bar and also to force the ends of the sleeve inwardly of the aperture therebetween and against opposite sides of the bar, thereby to clamp the cutter blade upon the bar, said clamping devices being separately adjustable so that by tightening one clamping device and slacking the other clamping device said cutter blade is caused to rock upon the bar and change the cutting radius of the cutter blade.

RALPH W. HENNINGS. 

